STATS 503 EXAM 1 QUESTIONS AND ANSWERS WITH COMPLETE SOLUTIONS VERIFIED GRADED A++

STATS 503 EXAM 1 QUESTIONS AND ANSWERS WITH COMPLETE SOLUTIONS VERIFIED GRADED A++ variation an inherent component of all living systems system Anything composed of multiple interacting parts sampling error the variation in results from multiple replications of the same study, due to random chance census collect data on every individual that exists model simplified representation of some part of the real world inference a generalization that you can make about a large group based on logic and evidence (data) collected on a few members of the group statistical inference a set of formal mathematical procedures used to make valid generalizations study population the collection of all individual units that we want to draw conclusions about sample a smaller group selected from the population, that we actually observe and collect data on sample units the members of the population statistical sample a group of specimens collected from the same study population variable the characteristics of individuals in the sample that we observe or measure distribution a mathematical function that describes the relative commonness or rarity of different values for a variable in a group statistically related knowing the value of one variable tells us something about the distribution of the other variable parameters quantities that summarize the distribution of a variable in a population statistic a quantity that is calculated from data parameter estimate describe our best guess for the value of a parameter based on the available data point estimate the single value that represents our best guess standard error quantifies our uncertainty about the point estimate confidence interval a pair of values that have a specified chance of containing the true value formal hypothesis test evaluates the probability that our data would occur if a set of assumptions about the population are true biological model describes physical and casual relationships that exist between different parts of a living system, explains how we think the system works, makes specific testable predictions statistical model an equation or set of equations that: - describes the distribution of a variable in a population - describes functional relationships among variables - allows valid inferences despite sampling error parametric model assumes that the distribution of a variable in the population follows a specific functional form nonparametric method do not assume that the distribution of a variable in the population follows any particular functional form data